Switch



April 26, 1927. 9 Z

J. F. HARRINGTON SWITCH Filed Dec. 51, 1923 gmuew co c Patented Apra 26,1927.

UNITED STATES JESSE F. HARRENGTON', F MEMPHIS, TENNESSEE.

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Application filed December 31, 1923.

My invention relates to an electric switch designed particularly for usein radio sets but adapted also for use in switches of numerous types. Itan object of my invention to provide a device of this character in whichthe contact point will be held securely in engagement with little or nowear due to adjustment of the switch. I

A further object of the invention is to provide a switch in which thecontacts will be held resiliently in engagement and in which the springtension will not be diminished with use.

Referring to the accompanying drawings, which are made a part hereof andon which similar reference characters indicate similar parts Figure l isan end elevation of my device.

Figure 2, a side elevation.

lln the drawings reference character 10 indicates a disk in which aresupported a plurality of contacts 11 having stems 12 with threaded endscarrying nuts 13 and lock nuts 14, means being provided for at tachmentof a connector to each contact in any conventional or desirable manner.A plate or bar 15 is spaced from the disk 10 and secured thereto inordinary manner by a bracket having arms fastened at their ends to theplate 15 by bolts 17.,

A shaft 18 passes through the parts 15 and 10 and carries at one end abutton or hand; wheel 19 with a pointer 20 attached thereto. At theother end the shaft has secured thereto a contact in the form of a leafspring 21 bent down at its end as shown at 22 for edge contact with anyone of the contacts 11. Conductors are connected to each of the contacts11 and to the contact 21 in any conventional or desirable manner. At theunder side the contact 21 has a longitudinal rib 23 bearing on anannular flange secured to the under face of the plate 10 or formedintegral therewith. The plate hasnotches 2 1 at intervals said notchesbeing separated by elevated parts 25.

Mounted on the shaft 18 adjacent the inner side of the disk 10 is aconcavo-convex spring plate 26 preferably of circular form and providedwith radial notches to permit the same to be more easily flexed. Saidspring plate is confined between a collar 27 held by a set screw 28 onthe shaft 18 and the body 10; I preferably provide a. bearing washer ofcopper or the like material between the collar and the spring plate.

Serial No. 683,75'Zf.

By this construction the collar 27 n1 ay be achusted longitudinallyofthe shaft 18 to.

1n the use of the device it will'be evident I that any rotation of thecontact- 18 will cause the rib 23 to travel over the flange whereuponthe high parts of the flange will lift the end 22 of the contact 21 awayfrom the contacts 11. The high places are so arranged as to fall betweencontacts 11 to lift the end 22 while the low places are arrangedopposite the respective contacts 11 to permit the end 22 to engagetherewith. in this way l prevent frictional engagementof the blade-likeend 22 with the disks 11 during the rotary movement and thus do awaywith the major portion of the wear on said parts, which ordinarilycauses grooves to be formed in the contacts 11. The spring contact 21 isalso not liable to become weak as is commonly the case with the helicalsprings ordinarily in use. Both the weakening of the spying and thewearing of contacts 11 cause poor connections and inetticient operation.

It will be obvious to those skilled in the art that various changes maybe made in my device without departing from the spirit of the inventionand therefore I do not limit myself to the specific device shown in thedrawings and described in the specification but only as indicated in theappended claims.

Having thus fully described my said invention, what l claim as new anddesire to secure by Letters Patent, is:

1. A switch comprising a disk of insulating material having anintegrally formed annular extension at one side said extension beingprovided with a corrugated end surface, contacts located around theperiphery of said disk outwardly of said corrugated extension, a shaftextending through said disk concentrically of said extension an arm onsaid shaft extending across said extension and having its'outer endinturned for engagement with said contacts, said arm having its underportion directly engaging the corrugations on the extension to cause thearm to ride up or down as the inturned end portion passes from onecontact to another, substantially as set forth.

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2. A switch comprising adisk of insulating' material having a concentricextension formed integrally on its underside the extremity of saidextension being provided with a corrugated surface, contacts spacedaround said disk adjacent the periphery thereof and outwardly of saidextension. said contacts being located opposite the depressions betweenthe corrugations, a. shaft extending through said disk concentrically ofsaid extension, a sleeve fixed on said shaft on the side of the diskopposite said concentric extension for limiting the endwise movement or"the shaft, an arm on the end of the shaft extending across saidextension and having ts outer end intnrned for enfrom one contactagainst the action of said sleeve and downwardly onto the next contactand a pointer on the oppositeend of said shaft from said arm,substantially as set forth.

In witness whereof, I have hereunto set my hand at Memphis, Tennesseethis 22 day of December, A. D. nineteen hundred and twenty-three.

JESSE F. HARRINGTON.

